Ela the Distance Matrix of a Bidirected Tree
نویسندگان
چکیده
The distance matrix of a tree is extensively investigated in the literature. The classical result concerns the determinant of the matrix D (see Graham and Pollak [7]), which asserts that if T is any tree on n vertices then det(D) = (−1)(n− 1)2. Thus, det(D) is a function dependent only on n, the number of vertices of the tree. The formula for the inverse of the matrix D was obtained in a subsequent article by Graham and Lovász [6] who showed that D = (e − z)(e − z) 2(n− 1) − L 2 . This result was
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